/*
* list.h List Utilities
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation version 2.1
* of the License.
*
* Copyright (c) 2003-2006 Thomas Graf <[email protected]>
*/

#ifndef __LIST_H
#define __LIST_H

struct list_head {
struct list_head *next;
struct list_head *prev;
};

static inline void list_add(struct list_head *obj,
struct list_head *prev,
struct list_head *next)
{
prev->next = obj;
obj->prev = prev;
next->prev = obj;
obj->next = next;
}

static inline void list_add_tail(struct list_head *obj,
struct list_head *head)
{
list_add(obj, head->prev, head);
}

static inline void list_add_head(struct list_head *obj,
struct list_head *head)
{
list_add(obj, head, head->next);
}

static inline void list_del(struct list_head *obj)
{
obj->prev->next = obj->next;
obj->next->prev = obj->prev;
obj->next = obj->prev = obj;
}

static inline void list_replace(struct list_head *old,
struct list_head *obj)
{
obj->next = old->next;
obj->next->prev = obj;
obj->prev = old->prev;
obj->prev->next = obj;
}

static inline int list_empty(struct list_head *head)
{
return head->next == head;
}

#define list_entry(ptr, type, member) \
container_of(ptr, type, member)

#define list_first_entry(ptr, type, member) \
container_of((ptr)->next, type, member)

#define list_at_tail(pos, head, member) \
((pos)->member.next == (head))

#define list_at_head(pos, head, member) \
((pos)->member.prev == (head))

#define LIST_HEAD(name) \
struct list_head name = { &(name), &(name) }

#define list_for_each_entry(pos, head, member) \
for (pos = list_entry((head)->next, typeof(*pos), member); \
&(pos)->member != (head); \
(pos) = list_entry((pos)->member.next, typeof(*(pos)), member))

#define list_for_each_entry_safe(pos, n, head, member) \
for (pos = list_entry((head)->next, typeof(*pos), member), \
n = list_entry(pos->member.next, typeof(*pos), member); \
&(pos)->member != (head); \
pos = n, n = list_entry(n->member.next, typeof(*n), member))

#define init_list_head(head) \
do { (head)->next = (head); (head)->prev = (head); } while (0)

#endif /* __LIST_H */